I've been going in circles trying to get this straight in my head, and I haven't found anything in the rules forum that covers it.

It seems to me there's a contradiction between the rules and the PAC. But I'm equally open to the fact that I'm just being really dumb.

I'm playing through a scenario. A tank is firing at an adjacent gun.

Rulebook (20.5) says "If the necessary [prof] checks are passed, roll using the gun/vehicle's 2nd FP and modifiers from the V/GUN column of the PAC ." (Emphasis mine.)

So, going by that, if the second FP of my tank is 8, I'm rolling against FP 8. If the gun happened to be in any terrain, that would reduce my firepower. I don't, however, get any FP benefit for being adjacent. If I roll an 8 or lower, I get a suppression on the Gun, and if I can add the 2nd casualty number of the gun to my roll, then the gun would be eliminated.

However, the PAC says "Gun/Vehicle vs Infantry/Guns : When Proficiency does not need to be checked, roll against the Infantry Firepower using modifiers from the table " (Emphasis mine.)

Two issues from this line:

1) Does "when proficiency does not need to be checked" mean "when proficiency has been passed, or does not need to be checked..." ? I.e., there's no different way to treating FP in this situation based on whether or not I've had to pass a proficiency check to fire, right?

2) The PAC seems to be telling me to use the Inf FP column of the table, which would give me +3 for being adjacent. This contradicts the rules, as I read them.

Oooof. Sorry for this long post. I hope I've made clear the nature of my uncertainty here. Can anyone clarify the rules for me, and perhaps clear up my misunderstanding?

'When Proficiency does not need to be checked' should probably read 'When Proficiency has (if necessary) been checked...'. There is no difference in the Effect resolution related to whether the Prof Check required a die roll.

You use the Infantry FP (second number) of the Vehicle or Gun and the V/Gun FP column of the PAC, which correctly tells you that there is no bonus for adjacency. It seems to be properly described in rule 20.5